Lower and Higher Heating Values of Fuels
You can use this calculator to obtain the heating value of a given mass or volume of hydrogen or other fuels, or to calculate the mass or volume given a certain heating value. Choose whether you want to convert to heating value or to mass/volume, and then choose the fuel type. Then enter the value you want to convert and its units, and click Convert to initiate the conversion.
The lower heating value (also known as net calorific value) of a fuel is defined as the amount of heat released by combusting a specified quantity (initially at 25°C) and returning the temperature of the combustion products to 150°C, which assumes the latent heat of vaporization of water in the reaction products is not recovered.
The higher heating value (also known gross calorific value or gross energy) of a fuel is defined as the amount of heat released by a specified quantity (initially at 25°C) once it is combusted and the products have returned to a temperature of 25°C, which takes into account the latent heat of vaporization of water in the combustion products.
- Btu = British thermal units; scf = standard cubic feet.
- The heating values for gaseous fuels in units of Btu/lb are calculated based on the heating values in units of Btu/scf and the corresponding fuel density values. The heating values for liquid fuels in units of Btu/lb are calculated based on heating values in unit of Btu/gal and the corresponding fuels density values.
- The heating values in units of MJ/kg, are converted from the heating values in units of Btu/lb.
- For solid fuels, the heating values in units of Btu/lb are converted from the heating values in units of Btu/ton.
- Coal characteristics assumed by GREET for electric power production.
- Coal characteristics assumed by GREET for hydrogen and Fischer-Tropsch diesel production.
- The HHV figure for liquid hydrogen in Btu/gal is based on personal communication with Ye Wu of Argonne National Laboratory.
Sources: See Lower and Higher Heating Values of Hydrogen and Fuels.